Basically a dedicated Record Attack-like experience for speedrunning the game as a continuous chunk rather than ILs. Has several quality of life features.
Benefits include:
* An unambiguous real-time bar across the bottom of the screen, always displaying the current time, ticking up until you reach the ending.
* Disable the console (pausing is still allowed, but the timer will still increment).
* Automatically skip intermissions as if you're holding down the spin button.
* Show centiseconds on HUD automatically, like record attack.
* "Live Event Backups" - a category of run fit for major events like GDQ, where recovery from crashes or chokes makes for better entertainment. Essentially a modified SP savefile, down to using the same basic functions, but has its own filename and tweaked internal layout.
* "spmarathon_start" MainCfg block parameter and "marathonnext" mapheader parameter, allowing for a customised flow (makes this fit for purpose for an eventual SUGOI port).
* Disabling inter-level custom cutscenes by default with a menu option to toggle this (won't show up if the mod doesn't *have* any custom cutscenes), although either way ending cutscenes (vanilla or custom) remain intact since is time is called before them.
* Won't show up if you have a mod that consists of only one level (determined by spmarathon_start's nextlevel; this won't trip if you manually set its marathonnext).
* Unconditional gratitude on the evaluation screen, instead of a negging "Try again..." if you didn't get all the emeralds (which you may not have been aiming for).
* Gorgeous new menu (no new assets required, unless you wanna give it a header later).
Changes which were required for the above but affect other areas of the game include:
* "useBlackRock" MainCFG block parameter, which can be used to disable the presence of the Black Rock or Egg Rock in both the Evaluation screen and the Marathon Run menu (for total conversions with different stories).
* Disabling Continues in NiGHTS mode, to match the most common singleplayer experience post 2.2.4's release (is reverted if useContinues is set to true).
* Hiding the exitmove "powerup" outside of multiplayer. (Okay, this isn't really related, I just saw this bug in action a lot while doing test runs and got annoyed enough to fix it here.)
* The ability to use V_DrawPromptBack (in hardcode only at the moment, but) to draw in terms of pixels rather than rows of text, by providing negative instead of positive inputs).
* A refactoring of redundant game saves smattered across the ending, credits, and evaluation - in addition to saving the game slightly earlier.
* Minor m_menu.c touchups and refactorings here and there.
Built using feedback from the official server's #speedruns channel, among other places.
Please look at the merge request description for a full explanation, since I know the vanilla team has been hashing this out and I don't want to add fuel to the fire without at least presenting a solid case.
(oddly enough, this actually revealed some secret file dependencies previously included via r_things.h! I also needed to include d_player.h in r_skins.h itself it seems)
* Move the visitation flags, Record Attack/NiGHTS Attack data, and emblem checking to outside of Y_StartIntermission.
* Y_CleanupScreenBuffer never got called for maps which skip the intermission, leading to a small memory leak; this is now fixed by moving it to G_AfterIntermission.
* Y_FollowIntermission was just G_AfterIntermission with modeattacking specific behaviour, but this is desired for all places where G_AfterIntermission is called, so just merge this into G_AfterIntermission.
Notably, these changes are necessary because there are now three maps in the main SP campaign which do not end with traditional intermissions. As a result, this fixes an issue where Black Core's tracks are not available in the Sound Test (due to MV_BEATEN never being applied).
Also, since I was here: Remove "gotperfect" from recorddata_t. This is a duplicate of `mapvisited[gamemap-1] & MV_PERFECT` which uses more memory. I have kept the new spacing in the gamedata for compatibility with RC1 savedatas, but moved it across to the original method everywhere else.
* Show emblem requirement on record attack menu
* Use bigger emblems on the menu.
* Display your best number of collected rings in yellow if reached perfect bonus.
* Adjusted XTRA frames (again)
